BEC-BCS Crossover in “Magnetized” Feshbach-Resonantly Paired Superfluids

2005/08/31 by Daniel E. Sheehy, Leo Radzihovsky · 10 citations
Physics and Astronomy · #Atomic and Subatomic Physics Research #Atomic physics #Bose–Einstein condensate #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Cooper pair #Electron #Excited state #Fermi Gamma-ray Space Telescope #Fermi gas #Feshbach resonance #Hyperfine structure #Molecule #Pairing #Phase (matter) #Phase diagram #Physics #Population #Quantum mechanics #Quantum, superfluid, helium dynamics #Singlet state #Superconductivity #Superfluidity #cond-mat.stat-mech #cond-mat.supr-con

paper · pdf · doi:10.1103/physrevlett.96.060401

published as PRL 96, 060401 (2006) · 4 RevTeX pages, 2 figures. Minor changes from previous version

openalex publication_date 2006/02/13 · arxiv created 2006/02/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We map out the detuning-magnetization phase diagram for a magnetized (unequal number of atoms in two pairing hyperfine states) gas of fermionic atoms interacting via an s-wave Feshbach resonance (FR). The phase diagram is dominated by the coexistence of a magnetized normal gas and a singlet-paired superfluid with the latter exhibiting a BCS-Bose Einstein condensate crossover with reduced FR detuning. On the BCS side of strongly overlapping Cooper pairs, a sliver of finite-momentum paired Fulde-Ferrell-Larkin-Ovchinnikov magnetized phase intervenes between the phase-separated and normal states. In contrast, for large negative detuning a uniform, polarized superfluid, that is, a coherent mixture of singlet Bose-Einstein-condensed molecules and fully magnetized single-species Fermi sea, is a stable ground state.

Citations

• Prospect of creating a composite Fermi–Bose superfluid
• Observation of resonance condensation of fermionic atom pairs
• Resonance Superfluidity in a Quantum Degenerate Fermi Gas

Cited by

• Spin-Depairing-Induced Exceptional Fermionic Superfluidity
• BEC–BCS crossover, phase transitions and phase separation in polarized resonantly-paired superfluids
• Realizing Fulde-Ferrell Superfluids via a Dark-State Control of Feshbach Resonances
• Phase diagram of a polarized Fermi gas across a Feshbach resonance in a potential trap
• Enhancement effect of mass imbalance on Fulde-Ferrell-Larkin-Ovchinnikov type of pairing in Fermi-Fermi mixtures of ultracold quantum gases
• Superfluidity at the BEC-BCS crossover in two-dimensional Fermi gases with population and mass imbalance
• Phase structure of mass- and spin-imbalanced unitary Fermi gases
• Fermi surfaces and Luttinger’s theorem in paired fermion systems
• Strongly interacting Sarma superfluid near orbital Feshbach resonances
• Integrable Models for Asymmetric Fermi Superfluids: Emergence of a New Exotic Pairing Phase